1. Field of the Invention
The present disclosure is related to a refrigeration circuit. More particularly, the present disclosure is related to a refrigeration circuit having a sealed refrigerant charge holding area.
2. Description of Related Art
Refrigeration circuits are typically used in a number of devices in order to cool the temperature of ambient air. A typical refrigeration circuit contains at least a compressor, a condenser, a receiver, a series of valves, at least one evaporator, and a system charge which circulates throughout.
Periodically, various components of the circuit need to be serviced, repaired, and/or replaced. In order to do so, the system charge must be removed from the components that will need servicing. One method that is currently used to prepare the circuit for servicing is to drain all of the system charge from the circuit. The system charge can not be re-used and must be disposed of. Due to various environmental regulations, costs associated with the proper disposal of the spent system charge can be great. Therefore, this method may be undesirable.
A second method commonly used to prepare a circuit for servicing involves a “system pumpdown”. In a system pumpdown, the compressor compresses all of the system charge which is then stored in a designated area within the circuit. This is advantageous in that it avoids having to remove and dispose of the system charge thereby, avoiding disposal costs and costs associated with new system charge.
In order for a system pumpdown to be effective, the designated storage area must have sufficient volume in which to store the compressed charge. Problems arise, however, when modifications to the circuit are made within the designated area, that reduce the volume available for storage. For example, in some refrigeration circuits, the condenser is included in the designated storage area. Round tube and fin condenser (“RTF”) coils are frequently used in condensers. RTF coils have large internal volumes and provide sufficient space so that the compressed system charge can be stored within the storage area. However, when micro-channel heat exchanger (“MCHX”) coils are substituted for the RTF coils, there is a reduction in storage volume. The heat transfer coefficient is higher for MCHX type construction than for RTF, so whenever this type of replacement is made for coils of equal capacity the internal volume (storage area) will be reduced. Problems will, therefore, arise during a system pumpdown as there is not sufficient space to store the compressed system charge.
There exists a need for a refrigeration circuit that can compensate for modifications made within the designated area that reduce the volume available for storage during a system pumpdown. Specifically, there exists a need for a refrigeration circuit that can compensate for the reduction in storage volume within a designated area when micro-channel heat exchanger coils are substituted for pre-existing coils within the condenser. The present disclosure provides such a circuit.